1. Field of the Invention
The present invention relates to a connecting device for interconnecting a pair of connectors mainly used to connect an automobile wire harness.
2. Background
Referring to FIGS. 7-9, a conventional connector device includes a male connector a and a female connector b each having terminal metal fittings therein which are connected to each other when the two connectors a and b are connected together, as disclosed in Japanese Utility Model Publication No. 52-133993.
The male connector a includes a fitting operation lever c which is pivotally mounted to the male connector a so as to pivot about shaft d. The fitting operation lever c has a driving groove e in the front end portion thereof and an operation portion f in the rear end portion thereof. The operation portion f includes an engaging projection g at the distal end of the lever. After the lever is rotated clockwise to facilitate the interconnection of the connectors, the engaging projection g of the lever is engaged with an engagement portion g' provided in the male connector a to retain the connectors in the interconnected state. On the other hand, the female connector b includes on the outer surface thereof a driven pin h which opposes the driving groove e of the lever c.
In such a conventional connector device, the male and female connectors a and b are provisionally located with respect to each other in a position where the respective terminal metal fittings i and i' are aligned with each other. From this position, the fitting operation lever c is rotated, causing the fitting side wall e.sub.1 of the driving groove e to engage the driven pin h such that further rotation of the lever c causes the groove wall e.sub.1 to urge against the pin h. Therefore, as shown in FIGS. 8 and 9, the male and female connectors a and b are completely fitted with each other. In this state, the engaging projection g rotates beyond the engagement portion g', resulting in the male and female connectors being engaged and locked together.
However, as shown in FIG. 8, occasionally the fitting operation lever c is not rotated sufficiently far to engage the engaging projection g with engagement portion g'. Since it is difficult to visually confirm that the lever is locked, the connectors are often secured to each other in an un-locked state. During operation, the vibration generated by the automobile causes the connectors to become slightly disconnected from each other resulting in poor electrical contact between the connectors.
The reason that the lever is prematurely stopped before it reaches the locked position is because the contact resistance of the terminal metal fittings i and i' reaches a maximum when the connectors approach the completely locked state. In addition, there is an added resistance associated with moving the engaging projection g over the engagement portion g'. As a result, a relatively large force is required causing an operator to mistakenly believe that complete fitting is achieved. Further, if the operation is stopped in a state shown in FIG. 8, then gravity acts on the fitting operation lever c tending to rotate it in the opposite, un-locking direction. Accordingly, contact resistance between the terminal metal fittings i and i' prevents the male and female connectors a and b from further moving. Moreover, the driven pin h is in close contact with both the fitting side wall e.sub.1 and disconnecting side wall e.sub.2 of the driving groove e, so that the fitting operation lever c is left in the above mentioned state (i.e., in the position illustrated in FIG. 8).
An object of the present invention is to eliminate the drawbacks found in the above-mentioned conventional connecting device. Accordingly, it is an object of the invention to provide a connector device which, when the rotational operation of a fitting operation lever is prematurely interrupted so that the operating lever is disposed in an interrupted position before the connectors are completely fitted and locked, allows the interrupted position of the lever to be readily viewed from the outside and thereby prevents the incomplete fitting of the connectors.